Drifting mine self protection system

ABSTRACT

This invention discloses a system to protect bow loading small craft from floating mines. The invention is characterized by a rake like fender held in front of the craft with vertically disposed mine engaging members depending downwardly into the water from a horizontal member. The fender is held to the front of the craft by a ball hitch and guy wires in such a manner that the action of the bow ramp is unobstructed. Further, the unit may be quickly removed from the craft to permit normal on and off loading of cargo.

United States Patent 15] 3,656,447 [4 1 Apr. 18, 1972 Sniffin [54] DRIF TING MINE SELF PROTECTION SYSTEM [72] Inventor: Millard T. Sniifin, Panama City, Fla. [73] Assignee: The United States of America as represented by the Secretary of the Navy [22] Filed: Dec. 3, 1970 [21] Appl. No.: 94,811

52 us. Cl. ..114/24o k [51] Int. Cl ....B63g 9/00 58] Field of Search ..l 14/240 R [56] References Cited UNITED STATES PATENTS 2,314,781 3/1943 Ganis ..1 14/240 R 2,969,762 1/ 1961 Livermore ..l l4/240 R Primary Examiner-Trygve M. Blix Attorney-Richard S. Sciascia, Don D. Doty and William T. Skeer [5 7] ABSTRACT This invention discloses a system to protect bow loading small craft from floating mines. The invention is characterized by a rake like fender held in front of the craft with vertically disposed mine engaging members depending downwardly into the water from a horizontal member. The fender is held to the front of the craft by a ball hitch and guy wires in such a manner that the action of the bow ramp is unobstructed. Further, the unit may be quickly removed from the craft to permit normal on and off loading of cargo.

10 Claims, 2 Drawing Figures PATENTEBAPR 181972 3,656,447

Ill/hr .7 fir/#09 wa /Wm Z/wu fig DRIFIING MINE SELF PROTECTION SYSTEM STATEMENT OF GOVERNMENT INTEREST FIELD OF THE INVENTION This invention relates to the field of naval architecture as it pertains to marine mine countermeasures. More particularly, the invention relates to a structure that may be applied to existing surface vessels to protect them against floating type marine mines. The nature of the structure permits installation on vessels when they are in theaters of operation where such mines might be encountered and removal therefrom for operation in areas where such mines are not a threat.

Floating type marine mines are a particular hazard to river and harbor surface craft. These mines may be planted from open boats or even from the shore by small groups of people. The mine floats on the surface, or slightly therebelow, and is arranged to detonate upon contact. A variety of firing mechanisms and buoyancy arrangements are readily improvised in the field by espionage personnel engaged in planting the mines. It is, therefore, easy for the mines to be planted by personnel apparently engaged in normal activities such as fishing, for example, or under the cover of darkness and, consequently, these mines are often encountered in waters previ ously cleared of these weapons.

Despite their simplicity, these mines pose a serious and constant threat to surface water craft engaged in patrol or supply missions. The mines low visibility, due to its smallsize and low position in the water, makes avoidance techniques ineffective. Consequently, persons engaging in these normal activities do so at great peril and with considerable apprehension and uncertainty.

DESCRIPTION OF THE PRIOR ART Because of the limited effective range of the mines, a satisfactory solution for individual surface craft is to cause their detonation at a range where they are relatively harmless. This may be satisfactorily accomplished by a structure extending foreward of the vessel and extending downwardly into the water. Such a device intercepts the mine at a distance foreward of the prow of the vessel which is beyond its effective range. The mine usually detonates upon contact with such structures venting its explosive power harmlessly in a water spout and leaving the protected vessel intact.

An example of this type of prior art device is shown in U. S. Pat. No. 2,314,781 issued to H. .l. Gains on Mar. 23, 1943, for a Marine Mine Destroyer." Such devices are useful for the older type of marine mines which were used upon the high seas and were moored in place to be detonated by ship contact. These devices extended far foreward of the vessel because of the great charge of explosive material used in these mines.

While unsatisfactory on the open seas, these prior art devices are, in many ways, unsatisfactory for river and harbor craft. The hydrodynamic drag of the prior art devices is great and markedly reduce the performance of the small modestly powered vessels used in riverine service. More important than the power they consume, however, is the adverse effect they have on the steering of the craft on which they are installed and the length of time that their installation and removal requires.

This is particularly true in the case of small landing craft and other vessels with bow loading unloading ramps. Such vessels, to perform their normally assigned missions, must be able to off and on load cargo and personnel with a minimum delay of time expended at the beach head or river landing. The importance of minimum expenditure of time expended in cargo handling cannot be better emphasized than pointing out that these operations are conducted in view of enemy artillery.

Further, the impairment of maneuverability which would necessarily accompany the use of the prior art devices would make steering the craft to the desired landing difficult. So great are the difliculties of using the prior art devices in bow ramp equipped landing craft and riverine craft, these craft are operated without any form of self defense and thereby exposed to the risks of destruction by floating mines.

SUMMARY OF THE INVENTION This invention overcomes the disadvantages of the prior art arrangements by providing an improved fender to protect vessels from floating riverine mines. The device of the invention is characterized as being of low mass, easily attached and removed, of very low drag, self supporting, and effective against the class of mines previously described. These laudatory characteristics are provided by the structure of the device in a manner which will be clearly described herein.

The structure comprising the improved system of the invention is characterized by simple mine engaging members, single rigid mounting tongue, quick disconnect ball and socket type of mounting, and quick disconnect flexible guy line tensioners.

- The precise fashion in which these features are combined and the manner in which they cooperate so as to provide the improved results are more fully described in connection with the I figures illustrating a preferred embodiment of the invention.

An object of the present invention is, therefore, to provide an improved defense against floating marine mines.

Another object of this invention is the provision of a bow mounted fender to intercept and detonate floating mines.

A further object of this invention is a mine intercepting and detonating structure extending forewardly of a surface vessel protected thereby to provide protection from collision with floating objects which are on the course of the vessel.

A further object of the invention is to provide a bow mounted mine fender having low hydrodynamic drag.

still another object of the invention is the provision of a bow mounted mine fender to be pushed through the water by a vessel to be protected thereby without impeding the maneuverability thereof.

A further object of the invention is to provide a bow mounted mine fender which may be installed and removed with a minimum crew and with a minimum expenditure of time.

Yet another object of the invention is to provide a bow mounted mine fender which may be attached to a vessel with a bow loading ramp.

Still another object of the present invention is a bow mounted marine mine fender which has low drag and low resistance to lateral motion such as that generated by the vessel comming about in a small radius.

A further object of the invention is to provide a bow mounted, float supported fender for marine mines which permits a ship on which it is installed to maneuver without restriction.

Other objects and many of the attendant advantages will be readily appreciated as the subject invention becomes better understood by reference to the following detailed description, when considered in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates the device of the invention installed on a surface vessel; and

FIG. 2 illustrates in elevation the mounting details of the system together with the mine engaging and buoyancy details of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. I, a vessel 11 is shown with the device of the invention installed thereon. As may be seen, vessel 11 has a bow ramp 12 at the bow end thereof. Ramp 12 is hingedly mounted so that it may be lowered to facilitate the loading and discharge of cargo and personnel thereover. Mine fender 13, the subject of the invention, is shown as attached to the bow of vessel 11.

Although the device of the invention and the method of mine defense made possible thereby are shown and described as they pertain to a landing vessel, it should be clearly understood that the invention is equally applicable to other types of marine vessels. For example, the mine fender of the invention may be used on lighters, barges, and other similar type vessels.

Fender 13 comprises a horizontal member 14 which supports a plurality of mine engaging elements, to be more fully described herein, and is attached to vessel 11 by a push bar 15. Diagonal braces 16 extend from the ends of horizontal member 14 to push bar 15 to promote rigidity of the system.

Referring to HO. 2, push bar 15 is shown as being terminated at its bitter end by a ball socket assembly 18. Socket assembly 18 cooperates with a ball hitch 19 mounted on the bow of vessel 11. Ball hitch 19 is mounted below ramp hinge 21 so as not to interfere with the action of bow ramp 12. Socket assembly 18 and mating ball hitch 19 may be of any suitable construction and those intended for the towing of land trailers have proven satisfactory in developmental studies. The principal consideration in the selection of suitable units is the ease of making and breaking the connection therebetween.

Extending downwardly from each diagonal brace 16 support arms 22 attach floats 23 thereto. The length of arms 22 are chosen so as to position floats 23 in supporting position. That is, arms 23 are chosen to support horizontal member a predetermined distance above the surface of the water. The particular height above the water surface is determined in accordance with the type of vessel being protected and the specific mine engaging members used by the system.

Arms 23 are shown as fixed length units which are permanently attached to diagonal braces 16. it is more convenient to make them in this manner especially where a single class of vehicle is involved such as in the case oflanding craft. In most instances where such craft are used, there are a large number of identical vessels in use in the same operation. For general use with a wide variety of surface craft, arms 22 may be made of adjustable length. This may be accomplished by making the arms telescoping or by letting them extend above braces 16 and securing them thereto by inserting fasteners into one of a series of holes provided in arm 23. Other known mechanical arrangements may be used to provide the desired degree of adjustment to place mine fender 13 at the desired height, if desired.

The mounting of floats 23 on diagonal braces 16 permits their positioning behind the mine engaging structure provided by horizontal member 14 and the mine engaging members, which will be more fully described herein. In this position they are protected from contact by the mine in the same fashion as vessel 11. Support arms 22, as stated above, may be adjustable in length to provide buoyancy at the desired height above the water.

Socket assembly 18 and ball hitch 19, if left unassisted, would permit mine fender 13 to pivot laterally and go to one side of vessel 11. To prevent this pivoting action from rendering mine fender inoperative, guy wires 17 are installed between eyes 24, mounted on diagonal braces 16 near the outboard ends of horizontal member 14, and eyes 25, on either side of the bow of vessel 11. To facilitate rapid attachment of mine fender 13, guy wires 17 are attached to eyes 25 by means of toggle purchases 26. Eyes 24 may, if desired, be mounted directly on horizontal member 14.

Toggle purchases 26 are conventional mechanisms used for a variety of purposes in the marine arts, such as lashing deck cargo, for example. By operating a lever the length of the line attached thereto is shortened a predetermined amount and, therefore, placed under a predetermined tension. In the system of the invention their use is preferred because of the speed at which they may be applied and released. If desired,

however, other types of line fasteners may be used such as a conventional hook and turnbuckle arrangement.

Horizontal member 14 supports a plurality of mine engaging members 27 which extend downwardly therefrom. Mine engaging members may be simply cylindrical rods threaded and soldered at the uppermost end so as to be secured by threaded fastener 28. Other types of mine engaging members may be used in place of members 27, if desired, but, the simple rod form, as shown in FIG. 2, have proven satisfactory. The lower portion of members 27 may be inclined forewardly, as shown, so as to lift encountered mines and other debris upwardly. Mines not detonated upon contact may often times be detonated by small arms fire when pushed to the surface.

The materials from which the device of the invention may be constructed are not critical. However, the use of lightweight metals, such as aluminum, is preferred. If desired, the hollow voids in the center of aluminum tubing may be filled with a buoyant foam plastic to insure flotation of component parts of the system should they become separated as might happen ifit successfully detonates a marine mine.

The foregoing description of a preferred embodiment of the invention, while sufficient for one skilled in the marine engineering and navel architecture fields to make and use the invention, may be better understood in view of the following preferred mode of operation and claims.

MODE OF OPERATION Upon entering waters known or believed to contain floating mines, mine fender 13 is attached to the bow of vessel 11. Socket assembly 18 is placed over ball hitch l9 and made fast thereto. Guy wires 17 are then fixed to eyes 25 on either side of the bow of vessel 11. Such an attachment makes mine fender 13 rigidly mounted on the bow of vessel 11 to be pushed through the water therebefore.

The absence of any large plane surfaces on mine fender 13 often permits it to survive a mine explosion which would be of such severity as to sink vessel. Should, hoever, the fender be damaged or bent until it interferes with the operation of vessel 11, it may be set adrift quickly.

Upon approaching a landing area, personnel from within vessel 11, or from the shore, enter the water and disconnect socket assembly from hitch 19. Guy wires 17 are removed from eyes 25 by operation of toggle purchases 26 and the entire fender may be pushed aside. Two men may accomplish this operation in less than a minute and therefore introduce a minimum of delay of the normal function of the vessel. The device, of course, may be easily reinstalled for return trips through the mine infested waters.

Obviously, other embodiments and modifications of the subject invention will readily come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing description and the drawings. It is, therefore, to be understood that this invention is not to be limited thereto and that said modifications and embodiments are intended to be included within the scope of the appended claims.

What is claimed is:

l. A drifting mine protection system for surface watercraft comprising in combination:

mine engaging means extending downwardly into the water for contacting and causing the detonation of floating marine mines;

support means attached to said mine engaging means for mounting a plurality thereof as a unitary geometrical configuration;

push bar means connected to said support means for transmitting propulsive force thereto;

socket assembly means attached to said push bar means and shaped so as to cooperate with a complementary shaped hitch means attached to the bow of said watercraft for providing quickly separable driving connection therebetween;

float means effectively connected to said support means in such manner as to be located at the rear thereof and to said push bar means for buoyant support thereof; and

guying means effectively connected between said support means and said watercraft for establishing a predetermined attitude relationship therebetween.

2. A drifting mine protection system according to claim 1 in which said support means comprises a horizontal metallic tubular member.

3. A drifting mine protection system according to claim 1 further comprising means connected between said support means and said push bar means for the bracing thereof.

4. A drifting mine protection system according to claim 3 further comprising support arm means attached to said bracing means and extending downwardly therefrom for providing mounting attachment points for the aforesaid float means.

5. A drifting mine protection system according to claim 1 in which said mine engaging means comprise cylindrical rods.

6. A drifting mine protection system according to claim 5 in which the lower portions of said mine engaging means extend foreward of the aforesaid support means.

7. A drifting mine protection system according to claim 5 in which said cylindrical rods are threaded at their upper extremities for facilitating attachment to the aforesaid support means.

8. A drifting mine protection system according to claim 1 in which said guying means comprises a flexible wire rope.

9. A drifting mine protection system according to claim 8 further comprising toggle means joined to said guying means for selectively applying or relieving tension therein.

10. A drifting mine protection system according to claim 9 in which said toggle means releasably engages eye means on said watercraft. 

1. A drifting mine protection system for surface watercraft comprising in combiNation: mine engaging means extending downwardly into the water for contacting and causing the detonation of floating marine mines; support means attached to said mine engaging means for mounting a plurality thereof as a unitary geometrical configuration; push bar means connected to said support means for transmitting propulsive force thereto; socket assembly means attached to said push bar means and shaped so as to cooperate with a complementary shaped hitch means attached to the bow of said watercraft for providing quickly separable driving connection therebetween; float means effectively connected to said support means in such manner as to be located at the rear thereof and to said push bar means for buoyant support thereof; and guying means effectively connected between said support means and said watercraft for establishing a predetermined attitude relationship therebetween.
 2. A drifting mine protection system according to claim 1 in which said support means comprises a horizontal metallic tubular member.
 3. A drifting mine protection system according to claim 1 further comprising means connected between said support means and said push bar means for the bracing thereof.
 4. A drifting mine protection system according to claim 3 further comprising support arm means attached to said bracing means and extending downwardly therefrom for providing mounting attachment points for the aforesaid float means.
 5. A drifting mine protection system according to claim 1 in which said mine engaging means comprise cylindrical rods.
 6. A drifting mine protection system according to claim 5 in which the lower portions of said mine engaging means extend foreward of the aforesaid support means.
 7. A drifting mine protection system according to claim 5 in which said cylindrical rods are threaded at their upper extremities for facilitating attachment to the aforesaid support means.
 8. A drifting mine protection system according to claim 1 in which said guying means comprises a flexible wire rope.
 9. A drifting mine protection system according to claim 8 further comprising toggle means joined to said guying means for selectively applying or relieving tension therein.
 10. A drifting mine protection system according to claim 9 in which said toggle means releasably engages eye means on said watercraft. 